Initial commit

.gitignore

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+target
+Cargo.lock

Cargo.toml

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+[package]
+name = "blake2-rfc"
+version = "0.1.0"
+authors = ["Cesar Eduardo Barros <cesarb@cesarb.eti.br>"]
+description = "A pure Rust implementation of BLAKE2 based on the draft RFC."
+repository = "https://github.com/cesarb/blake2-rfc"
+readme = "README.md"
+keywords = ["blake2", "blake2b", "blake2s", "hash", "hashing", "crypto", "cryptography"]
+license = "MIT"
+
+[dependencies]
+constant_time_eq = "0.1"
+
+[dev-dependencies]
+rustc-serialize = "0.3"

LICENSE

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+Copyright (c) 2015 Cesar Eduardo Barros
+
+Permission is hereby granted, free of charge, to any
+person obtaining a copy of this software and associated
+documentation files (the "Software"), to deal in the
+Software without restriction, including without
+limitation the rights to use, copy, modify, merge,
+publish, distribute, sublicense, and/or sell copies of
+the Software, and to permit persons to whom the Software
+is furnished to do so, subject to the following
+conditions:
+
+The above copyright notice and this permission notice
+shall be included in all copies or substantial portions
+of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF
+ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
+TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
+PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT
+SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR
+IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+DEALINGS IN THE SOFTWARE.

README.md

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+# blake2-rfc
+
+This is a pure Rust implementation of BLAKE2 based on the [draft RFC]
+for the BLAKE2 hash functions.
+
+[draft RFC]: https://tools.ietf.org/html/draft-saarinen-blake2
+
+## Design
+
+This crate follow the common API design for streaming hash functions,
+which has one state/context struct and three associated functions: one
+to initialize the struct, one which is called repeatedly to process the
+incoming data, and one to do the final processing and return the hash.
+For the case where the full data is already in memory, there is a
+convenience function which does these three steps in a single call.
+
+This basic design was slightly adapted to make a better use of Rust's
+characteristics: the finalization function consumes the struct, doing a
+move instead of a borrow, so the struct cannot be accidentally used
+after its internal state has been overwritten by the finalization.
+
+To prevent timing attacks, it's important that the comparison of hash
+values takes constant time. To make it easier to do the right thing, the
+finalization function returns the result wrapped in a struct which does
+a constant-time comparison by default. If a constant-time comparison is
+not necessary, the hash result can easily be extracted from this struct.
+
+## Limitations
+
+This crate is limited to the features described in the draft RFC: only
+the "digest length" and "key length" parameters can be used. Other
+advanced BLAKE2 features have not been implemented.
+
+A single BLAKE2b hash is limited to 16 exabytes, lower than its
+theorical limit (but identical to the BLAKE2s theorical limit), due to
+the use of a `u64` as the byte counter. This limit can be increased, if
+necessary, after either the `extprim` crate (with its `u128` type) or
+the `OverflowingOps` trait become usable with the "stable" Rust release.
+
+This crate does not attempt to clear potentially sensitive data from its
+work memory (which includes the state context, the stack, and processor
+registers). To do so correctly without a heavy performance penalty would
+require help from the compiler. It's better to not attempt to do so than
+to present a false assurance.

src/as_mut_bytes.rs

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+// Copyright (c) 2015 Cesar Eduardo Barros
+//
+// Permission is hereby granted, free of charge, to any
+// person obtaining a copy of this software and associated
+// documentation files (the "Software"), to deal in the
+// Software without restriction, including without
+// limitation the rights to use, copy, modify, merge,
+// publish, distribute, sublicense, and/or sell copies of
+// the Software, and to permit persons to whom the Software
+// is furnished to do so, subject to the following
+// conditions:
+//
+// The above copyright notice and this permission notice
+// shall be included in all copies or substantial portions
+// of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF
+// ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
+// TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
+// PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT
+// SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+// CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR
+// IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+// DEALINGS IN THE SOFTWARE.
+
+use std::mem;
+use std::slice;
+
+pub trait AsMutBytes {
+    fn as_mut_bytes(&mut self) -> &mut [u8];
+}
+
+macro_rules! as_mut_bytes_impl {
+    ($t:ty) => {
+        impl AsMutBytes for $t {
+            #[inline]
+            fn as_mut_bytes(&mut self) -> &mut [u8] {
+                unsafe {
+                    slice::from_raw_parts_mut(
+                        self.as_mut_ptr() as *mut u8,
+                        mem::size_of::<Self>())
+                }
+            }
+        }
+    }
+}
+
+as_mut_bytes_impl!([u32; 16]);
+as_mut_bytes_impl!([u64; 16]);